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51.
The natural history of lamivudine-resistant hepatitis B virus (HBV) infection in renal transplant recipients (RTx) is unclear, despite its increasing incidence. Twenty-nine HBsAg-positive RTx with rising HBV DNA received lamivudine therapy. The course of lamivudine-resistant HBV infection was studied prospectively. During 68.7 +/- 12.5 months of follow-up, 14 (48.3%) patients developed lamivudine resistance, at 10-35 months (mean 16.9 +/- 7.0). All showed mutant sequences at codons 552 and 528 of the YMDD motif, while 13 patients demonstrated wild-type sequence at codon 555. Lamivudine resistance was unrelated to patient demographics, HBeAg status/sero-conversion, or genotype. Following resistance, HBV DNA and alanine aminotransferase showed an initial increase followed by spontaneous gradual reduction. The subsequent peak HBV DNA was lower (1.26 +/- 1.09 x 10(9) vs. 6.26 +/- 12.23 x 10(9) copies/mL, p = 0.011), while that of alanine aminotransferase was higher (196 +/- 117 vs. 77 +/- 47 imicro/l, p = 0.005), compared with pretreatment levels. Post-resistance hepatitic flare occurred in 11 (78.6%) patients. This was transient in four (36.4%), but became chronic in six (54.5%) patients. Decompensation was noted in one patient during this flare, but all survived. We conclude that drug resistance is prevalent in lamivudine-treated RTx. Despite a lower ensuing peak viremia compared with baseline, hepatitic flare is common. While most patients have spontaneous resolution, a minority may develop potentially fatal decompensation during the preceding exacerbation.  相似文献   
52.
OBJECTIVE: The aim of this study was to determine whether the survival of patients with untreated synchronous liver metastases after resection of a colorectal cancer was associated with any features of the primary tumour. METHODS: Information for 398 consecutive patients with unresected liver metastases in the period 1971-2001 was examined by multivariate survival analysis. RESULTS: Of 19 clinical and pathological variables considered, survival was independently associated only with residual tumour in a line of resection (hazard ratio (HR) 1.95), venous invasion (HR 1.87), right colonic tumour (HR 1.68), lymph node metastasis (HR 1.54), and extra-hepatic metastasis (HR 1.16); 8.3% of patients had none of these adverse features. Their 2-year overall survival rate was 39.2%, compared with only 16.5% (P < 0.001) in those with one or more adverse features. CONCLUSIONS: These findings may assist in selecting patients most likely to benefit from treatment of hepatic metastases and in counselling patients and their relatives.  相似文献   
53.
The appearance of an acute effusion in a well-pneumatized temporal bone directs attention to the nasopharynx and skull base. Two patients are described in whom dehiscence of the temporomandibular joint allowed herniation of the contents of the joint posteromedically, where they obstructed the middle ear entrance of the eustachian tube, the protympanum. This is, to the authors' knowledge, a previously unreported cause of an acute middle ear and mastoid effusion.  相似文献   
54.
The clinical presentation and the biochemical and molecular genetic findings are described in a 13 year old Chinese boy with MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes). The diagnosis was initially suspected because of the characteristic clinical features and the strong family history of convulsions. Using polymerase chain reaction—restriction enzyme analysis, the heteroplasmic nt3243 A→G mutation in mtDNA of peripheral blood leucocytes and a muscle sample was demonstrated. The oligosymptomatic relatives were then screened by this method and the degree of heteroplasmy was analysed. This appears to be the first report of a MELAS family in Hong Kong with this described mutation. Molecular genetic techniques are advantageous in the diagnosis of MELAS.  相似文献   
55.
应用双光子及单光子吸收测定技术,检测了92名出生3d内的新生儿骨矿质含量,其中巨大儿30名,正常体重儿32名,低出生体重儿30名,其孕龄分别是40.1±0.7、39.1±1.5和37.4±1.2孕周。结果表明,巨大儿、正常体重儿、低出生体重儿的全身骨矿质含量分别是101.6±28.8、85.2±19.8、59.9±27.2g/cm2,巨大儿骨矿质含量最高,正常体重儿次之,低出生体重儿最低,差异有显著性(P<0.01)。颅骨、肱骨、股骨的骨矿质含量与全身的骨矿质含量有高度的相关性,相关系数分别是0.943、0.879和0.745(P<0.01)。全身的骨矿质含量与出生体重、孕龄及头围有高度相关性,相关系数分别是0.755、0.596和0.556(P<0.01)。提示颅骨、肱骨及股骨的任一部位均可代表全身的骨矿质含量,肱骨是确定全身骨矿质含量较好的部位,新生儿骨矿质含量受出生体重、孕龄及头围的影响较大。  相似文献   
56.
Immunopathologic study of Vogt-Koyanagi-Harada syndrome   总被引:9,自引:0,他引:9  
We studied an enucleated eye from a patient with a 30-year history of Vogt-Koyanagi-Harada syndrome using both conventional and immunohistochemical techniques. Clinically, the eye was in the end stage of Vogt-Koyanagi-Harada syndrome, and was characterized by the absence of inflammation, large areas of chorioretinal scarring, and pigmentary changes. Histopathologic examination showed marked retinal gliosis, extensive chorioretinal adhesion and scar formation, migration of pigment into the retina, and severe retinal pigment epithelial changes. However, foci of mild to moderate nongranulomatous inflammation of the uvea were observed. These foci contained infiltrating cells that were mainly T lymphocytes with B lymphocyte aggregates at the center. Scattered macrophages were also noted in the uvea and retina. These findings suggest that both the cell-mediated and humoral immune arms may play roles in the pathogenesis of Vogt-Koyanagi-Harada syndrome.  相似文献   
57.
We describe a 15-y-old girl with Fechtner-like syndrome, who is the first Chinese reported to have this rare syndrome. She presented with left homonymous hemianopia and neuroimaging revealed haemorrhage in both parietal and occipital lobes. Peripheral blood smear showed macrothrombocytopenia and intracytoplasmic inclusion bodies inside leucocytes. Thrombocytopenia and proteinuria responded to intravenous immunoglobulin and pulsed methylprednisolone. This case illustrates that life-threatening haemorrhage can occur in patients with Fechtner syndrome. Although there was no effective treatment reported in the literature, high dose steroid and immunoglobulin seemed to be useful in our patient. Our patient also had nephritic-nephrotic syndrome with renal insufficiency, which is unusual in adolescent female patients.  相似文献   
58.
Studies on the effectiveness of pain management have uniformly concluded that health care providers underestimate or undertreat pain. In the emergency department (ED) in which this study was conducted, physicians receive formal didactic and bedside teaching on pain recognition and management in order to heighten the awareness of patient's need for pain control. The purpose of this study was to determine if this outpatient pain management of patients with acute, painful conditions is better than that reported in the medical literature. In this prospective study, 110 adult patients who had an acute, painful diagnosis were telephoned 48 hours after discharge from the ED and asked if they felt their pain at home was well controlled. Patient satisfaction with pain control was higher (91%) than that reported in the medical literature. Also, pain medication was provided more frequently by this study's ED (95%). Education on pain awareness and treatment is a way to improve pain management.  相似文献   
59.
Studies of the ontogeny of IGF-I mRNA during embryonic and larval development of the gilthead sea breamSparus auratashowed its expression during these early developmental stages. The present study appliesin situhybridization to localize IGF-I and IGF receptor mRNAs in 16-day larvae ofS. aurata.Paraffin sections were hybridized with homologous RNA probes labeled by [35S]UTP. IGF-I mRNA expression was found mainly in chondrocytes, in both the gill arches and cranial cartilage, in skeletal muscle, in the brain, in the pancreas, in the retina, and in the epithelial cells surrounding the lens. A strong positive reaction for IGF receptor mRNA was found in skeletal muscle, in the pancreas, and in the lymphoid tissue found in the intertubular tissue of the kidney. Signals were less intense in brain and chondrocytes. It is suggested that in teleosts, as in higher vertebrates, IGF-I may be involved in the regulation of tissue growth and differentiation in an autocrine/paracrine manner.  相似文献   
60.
Although the leading causes of fever and pulmonary infiltrates in sickle cell patients are acute bacterial pneumonia and the acute chest syndrome, the former is usually responsive to antibiotics and not protracted, and the clinical course of the latter is short and self-limited. A patient with sickle cell anemia presented with fever and pulmonary infiltrates of several weeks duration that were unresponsive to antibiotics. Gross endobronchial abnormalities were noted on bronchoscopy, and the biopsies were consistent with sarcoidosis. The diagnosis of sarcoidosis can be difficult to establish in a patient with sickle cell anemia and protracted fever since both disorders are associated with chronic interstitial changes on the chest radiograph as well as restrictive physiology.  相似文献   
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